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Vintage Components - Simplex SLJ front derailleurs

On this page: Simplex Super LJ A 522 clamp-on

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Simplex founder Lucien Juy owned a bike shop in Dijon, France, when he began making his first derailleurs in 1928. His innovative designs were a hit and by 1933, Juy said he was making 40,000 derailleurs a year.

It wasn't until 1961 that Simplex adopted the deforming parallelogram that Campagnolo had popularized with its ground-breaking Grand Sport derailleur a decade before. But Juy's Simplex derailleurs had a sprung top pivot, the way all derailleurs are made today. At the time, that Simplex Export 61 was probably the best-shifting changer made.

A year later Juy decided to make Simplex derailleurs out of an acetal resin (OK, plastic) made by Dupont called "Delrin". It was a terrible mistake. Juy took what was the best derailleur in the world and turned it into a flimsy, delicate changer.

In the early 1970s Juy again began producing superb changers when he came out with the alloy Super LJ series. They were nicely finished, well-designed, good shifting derailleurs.

No amount of innovation or quality improvement could stem the Asian onslaught, exacerbated by association with those delrin derailleurs that came on so many bike-boom bikes. Simplex ceased production in the 1990s.

Simplex Super LJ A 522 clamp-on front derailleur. Used, $50.00

We believe this is the last version of the Super LJ front derailleur. The Simplex starburst logo was removed from the cage starting with 1984 production. This derailleur might have been made in 1985. It is a very good changer.

  • The derailleur was made with a snap-on spring cover that had the Simplex name. We do not have it.
  • Both Edco and Gipiemme sold this derailleur, produced by Simplex but carrying their logos.

Simplex LJ front derailleur

We can date this because the starburst logo is on the clamp, but not on the cage.

Simplex Super LF front derailleur

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